The Gifting Tree - Candi Ivy wants you to get a present from the Gifting Tree. Get a gift from under the tree, talk to Ivy, and get a Holiday Mystery Gift.

Bye-Bye Supplies! Once you've completed The Snowman Disassembly Quest, Candi Ivy will ask you to destroy more snowman making supplies. Complete the Crafty Robgoblins Mini-Game for a Holiday Mystery Gift.

Pretty Presents - Annabelle (located just east of the Gifting Tree) asks you to look around Snowhill for her missing presents for a Holiday Mystery Gift

Holiday Recital - Mayor Crystalline (located in front of Town Hall just North of the Gifting Tree) would like you to give the gift of music. Complete "Feeling the Beat" Mini-game (Located east of the Mayor, next to the Stage) on Musician Level Difficulty for a Holiday Mystery Gift.

Curious Gift Baskets - Downy (located just west of the Gifting Tree) needs you to cook up some curious creations for her Gift Baskets. Head to Lucca De'Flor's Cooking Table (just South of Downey) and cook up three Burnetta's Curious Creations. Return to Downy for a Holiday Mystery Gift.

Snowman Showdown - Everett (located west of Town Hall on the path the the Singing Crystals Mine) needs coal, but the only way to get them is by defeating snowmen who are trying to steal presents from the Gifting Tree. If you get 50 pieces of coal he'll trade you them for a Penguin Cookie (Turns you into a Snowball for 2 minutes)!

One-Time Quests:

Party Animal - Preston Daly (located next to the Sanctuary Warpstone) would like for you to deliver party invitations and will reward you with a Santa Hat.

Go west to the Pet Shop and deliver the first invite to Florina

Then head to Ikee (His shop is next door to the Costume Shop in Pixiewood) and deliver your second invitation.

Then port to the Vale of the Ancients and deliver the third invite to Sir Wellington (at the campsite just outside of the Vale).

Last ( But not least ) Port to Sacred Grove Shallows and see Reed Stillwater

Finally return to Preston for your gift!

Quest Lines:

Present Problems - Candi Ivy (near the Gifting Tree in Snowhill) would like you to find out why some snowhill residents are unhappy with thier presents. She'll award you five Fruitcakes for finding out.

Holiday Cheer - Candi Ivy would like you to /cheer up the gifting tree for five Eggnog.

Silversnow's Sapling - Candi Ivy would like to to speak to Silversnow (located up in the mountains, North of the Singing Crystal Mines) about what is wrong with the Gifting Tree. Silversnow asks you to harvest fresh Snowberry and Starnut which you can get at Perry's Pasture (in South Snowhill). After you fertilize the Gifting Tree, Candi Ivy gives you Subartic (Boys) or Alpine (Girls) Winterwear Gloves.

Guarding the Gifting Tree - Candy Ivy needs you to keep an eye out. Two "disguised" robgoblins look suspicious, ease drop on their conversation and report back to Candi for Subartic (Boys) or Alpine (Girls) Winterwear Boots.

The Perfect Disguise - (Member's Only Quest) Candi Ivy needs you to sneak into the robgoblin camp! Get the perfect disguise from Spindle (NW of Gifting Tree) - Dont forget to take a Portrait! You learn of the evil plans at the Robgoblin Camp (just South-East of the Snowhill Entrance). Report back to Candi Ivy for Subartic (Boys) or Alpine (Girls) Winterwear Pants.

Robgoblin Robbery Ring - Candi Ivy needs you to prevent the Robgoblins from making any more Snowmen! Complete the Crafty Robgoblins Mini-Game (See below) for Subartic (Boys) or Alpine (Girls) Winterwear Hat.

Unfortunately Snow Days also means the arrival of the Abominable Snowman and his snowmen henchmen. They show up every year to steal the presents from under the gifting tree! Protect the presents by clicking on the "Anti-Snowman Snowball Piles" near the gifting tree and throw the Snowballs (by pressing the number 3) at the Snowman Invaders and collect their coal. Then when the Abominable Snowman appears, snowball him as well and **** drop a chest. Click on the chest and get rewarded with a Holiday Mystery Gift!

Story Teller:

Dont forget to listen to the story of the History of the Holidays! You can find Miss Kara (the story teller) directly South of the Giving Tree teaching three children on the bank of a hill.

Also watch the Kids when the Snowmen invade!

Credits:

Thanks to Sammiebird101 for reminding me about Preston Daily's "Party People" Quest for the Santa Hat!

Thanks to Kessha for her post regrading 2010 Snowdays, which can be found here along with pictures of most the outfits, effects, etc.):

And thanks to all the others that contributed; Arianwyn for confirming the Gingerbread Sweater in 2011, Darian Spirithorn for pointing out the Snow Hog Pet Pal, Azure Coldlake for the correction to the 2010 Coin and Marketplace Items, Marisol Bluesurf for adding Eggnog and Fruit Cake to the 2011 Mystery Gift List, Queena for adding Toasty Gloves to the Brawler Prizes and Rugged Gloves to the Medic Prizes for the Crafty Robgoblins Mini-Game, Autumn Pixidust for showing me the Oversized Candy Canes (and being the best daughter ever!),

Just a couple of corrections for you...
~~Azure is right, Yule is SC (it's the brown nose version of the reindeer pet)
~~The Silver Sparkler is not new, it's been there for quite a while (the price is lower now, but not new)
~~And you can officially add Eggnog and Fruit Cake to the Mystery Gift list